The invention relates to a sanitary outlet element which can be inserted, by way of its insert housing, into the water outlet of a sanitary outlet fitting and has a jet regulator for shaping the exiting water jet, there being arranged in front of the jet regulator, as seen on the inflow side, a throughflow-quantity regulator or a throughflow restrictor, by means of which the quantity of water flowing per unit of time is adjusted, or limited, to a set value.
A wide variety of different designs of sanitary outlet elements arranged in a water line are already known. Therefore, jet regulators which can be inserted into the water outlet of a sanitary outlet fitting are already available. The previously known jet regulators, which can either be fastened directly in the water outlet of a sanitary outlet fitting or can be inserted into an outlet mouthpiece, which can be installed in the water outlet, usually have a jet divider, by which the water stream flowing in through the water line and the fitting body is subdivided into a multiplicity of individual jets. These individual jets, depending on the jet-regulator design, can be aerated, as required, before, in a homogenizing device downstream of the jet divider and/or in an outflow-side flow straightener having a mesh-like, lattice-like, screen-like or honeycomb-like structure, a homogeneous, soft and non-splashing water jet is formed at the water outlet.
In order for the jet regulator to function optimally and shape the water jet exiting from the water outlet, it is necessary to have a certain quantity of water flowing through the jet regulator. Since the jet regulator, and possibly also the downstream functional units of the jet regulator, form/forms a flow obstruction, there is a risk, at low pressures, of the quantity of water flowing through the jet regulator being insufficient, and the jet regulator not being able to perform its function, and of the water jet exiting from the jet regulator being felt to be uncomfortable.
U.S. Pat. No. 4,562,960 describes a sanitary outlet element which has a jet aerator, which has a throughflow-quantity regulator arranged before it, as seen in the flow direction. While the throughflow-quantity regulator has the task of adjusting the throughflowing water to a fixed maximum throughflow output, irrespective of pressure, the downstream jet aerator, as seen in the flow direction, is intended to form a homogeneous, effervescent-soft and non-splashing water jet. The throughflow-quantity regulator of the outlet element previously known from U.S. Pat. No. 4,562,960 has an annular flow-restricting body, which is made of an elastic material and delimits, between itself and an inner regulating body, a control gap which, as the pressure of the throughflowing water increases, narrows to an increasing extent such that, even as the pressure of the throughflowing water increases, a set maximum throughflow output is not exceeded. The water coming from the throughflow-quantity regulator of the previously known outlet element then flows through the downstream jet aerator, as seen in the flow direction. Said jet aerator has a jet divider, which divides up the inflowing water stream into a multiplicity of individual jets. The jet divider generating the separated water jets here constitutes a narrowing of the throughflow cross section, in which cross-sectional narrowing the individual jets generated experience acceleration such that a negative pressure arises on the outflow side of the jet divider, ambient air being sucked into the jet-regulator housing with the aid of said negative pressure, and the ambient air then being mixed with the individual jets before the individual jets aerated in this way are brought together again, in an outflow-side flow straightener, to form a homogeneous overall jet.
The throughflow-quantity regulator provided in the previously known outlet element does not mix a certain additional quantity of water in with a basic output of the outlet element at low water pressures, in order for this additional quantity of water to be fully suppressed at high throughflow outputs; rather, the previously known throughflow-quantity regulator merely adjusts the throughflow output to a set maximum value.